Discovery of Chlorine Chlorine was produced first in 1774 by Carl Wilhelm Scheele, who collected the gas released by the reaction of pyrolusite (manganese dioxide) with the substance we now call hydrochloric acid. It had, according to Scheele, "a very perceptible suffocating smell, which was most oppressive to the lungs... and gives the water a slightly acidic taste... the air in it acquires a yellow color..." Scheele also noted the reactivity and bleaching qualities of the new gas he had made: "all metals were attacked... fixed alkali was converted into common salt... all vegetable flowers - red, blue, and yellow - became white in a short time; the same thing also happened with green plants... insects immediately died. (1) Despite the accuracy of his observations, Scheele mistakenly thought the resulting gas was a compound that contained oxygen. Sir Humphry Davy in 1810, however, found he could not get the new gas to react with a charcoal electrode, which caused him to believe it may not contain oxygen. In reactions with phosphorus and ammonia, he demonstrated the new gas could not contain oxygen. He used a huge, 2000 plate voltaic pile (battery) to see whether he could get oxygen out of the gas's compounds with phosphorus and sulfur, but again found no oxygen. (1a) In 1811, Davy concluded the new gas was in fact a new element. (1b) He named it chlorine, from the Greek word 'chloros', meaning pale green.